Resistance unit.



No. 895,857. A PATENTED AUG. 11, 1908. J. L. R. HAYDEN.

RESISTANCE UNIT.

APPLICATION FILED MAR.29,1907.

Witnesses: Inventor:

163 Joseph LR. Hayden,

UNITED STATES. PATENT OFFICE.

JOSEPH L. R. HAYDEN, OF .SGHENEOTADY, NEW YORK, ASSIGNOR To GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

RESISTANCE UNIT. 1

Specification of Letters Patent.

Patented Aug 1 1, 190a.

Application flled March 29, 1907. Serial No. 365,301.

To all whom it may concern: I Be it known that I, JOSEPH LLB. HAYDEN,

. a citizen-of the United States, residing at Schenectad county of Schenectady, State of New York, have invented-certain new and useful Improvements in Resistance Units, of which the following is a specification.

This invention relates to resistance units for electric circuits and the process offorming the same, andhas' for its object the provisionof an inexpensive unit which will have a high resistance, stand a high temperature without injury, and which ma be connected in circuit in a reliable and e cient manner.

for many uses especially where a large amount of ener y is to be dissipated. One

of the reatest ifliculties, however, with the cast s' icon rod has been the formation of proper conducting terminals. The silicon rods are often operatedat a high tem erature', and the difficulty with the termina s has been that they either could not stand the temperature, or the different coefiicients of expansion. of 'the terminal and the silicon would cause an im erfect joint. I have found that a very e cient and inexpensive terminal for silicon rods may be made by causing the metal to unite or weld with the silicon so as to form an auto enic union between them. I have found t at an exceedingl efficient terminal may be formed by a pying an iron terminal to the rod and t en raising the temperature until there is a chemical reaction between the iron and the SlllCOIl whereby ferro-silicon is roduced.

The heating may be'accomplishe in many ways, one ofiwhich is to pass an electric current th ough the rod so as to .heat the same at the erminal.

Referring to the drawing, in which I have sh'own'one form of my invention, Figure 1 is 'an elevation partly in section, of my improved 50.

resistance unit mounted upon an insulating base; 21's a view of the rod and terminal, the latter being in section; and Fig. 3 is a sectional viewofthe rodwith the terminalappilied. v

eferring to the drawing, 10 1s a stick or rod of resistance material, preferably cast silicon, having enlarged ends adapted to receive the conductin terminal. For purpose of illustration, have shown this terminal in the form of a ca 11 which may beof any conducting metal, a though Ihave found that iron serves the purpose ver well. The cap is spun from sheet metal 0 a size large enough to fit easily over the enlarged end of v the rod... The temperature is then raised to a very bri ht or nearly white red heat. This may be one by passing a currentof sufiicient density to give the heat required, through the rod which is set in conducting clips 12 so that the current will pass from the clip to the terminal thence through the rod to the clip and terminal on the opposite end.

The high temperature causes the silicon and iron to chemically combine without either the iron or the silicon meltin i. e., there is no fusing together of the meta s. In this case, the elements combine to form ferrosilicon which binds the elements together in a perfect joint. In this way the rod and the terminal are autogenically united by a chemical union, and the joint will stand at least a bright red heat without injury and it will not be impaired by differences in coefiicients of ex ansion. I find the best results are obtained when the iron caps are not perfectly clean or free from oxid, as the latter acts after the manner of a flux in facilitating the union. of this character may be easily adapted for use in electric circuits, lightning arresters and the like by simply placing them in clips which 'are preferably yielding so as to allow ex ansion and contraction of the rod.

t is understood, of course, that various modificationsof the invention above described will suggest themselves to those skilled in the art without departing from the spirit of my invention, the scope of which is set forth in the annexed claims.

What I claim as new and desire to secure by Letters Patent of the United States, is,-

1. An electrical resistance comprising a cast silicon rod havin an iron termlnal in intimate conducting re ation thereto.

2. Ankelectrical resistance composed of silicon having amiron conducting terminal autogenically connected thereto. 7

3. An electrical resistance composed of cast silicon having an iron conducting terminal welded thereto.

Resistance sticks having terminals 4. An electrical resistance comprising a cast silicon rod having an iron cap welded thereto. a

5. An electrical resistance composed of silicon having a metallic terminal chemically united thereto.

6. An electrical resistance composed of.

cast silicon having a metallic terminal'chemically united thereto.

7. An electrical resistance com osed of cast silicon having an iron termina chemically united thereto.

8. An electrical resistance comprising a silicon rod, a metallic terminal thereon and a chemical compound of the silicon and the metal forming a joint between vthe rod and the terminal.

9. An electrical resistance com rising a silicon rod and an iron termiria secured thereto by a joint of ferro-silicon.

10. An electrical resistance comprising a silicon rod having an iron cap secured thereto by welding the two elements.

11. An electrical resistance comprising a silicon rod having a metallic cap secured thereto by chemically uniting the two elements. I

12. The process of forming a metallic terminal on a silicon rod, which consists in heat ing the metal in contact with the silicon un-- til there is a chemical action between the elements.

13. The process of securing a conducting terminal to cast silicon which consists in heatin the same in contact with each othe until t ey are chemically united.

14. The process of securing an iron terminal to a silicon rod, which consists in heating the same in contact with each other until a compound of iron and silicon is formed.

15. The process of securing a metallic terminal-to a silicon rod,'which consists in applying the terminal to the rod and passing a current through the joint to heat the same until a chemical reaction takes place.

16. The process of securing an iron termi nal ma siliconrod, which consists in applying the terminal to the rod and passing a current through the joint until ferro-sjlicon is formed between the elements.

In witness whereof, I have hereunto set my hand this 28th da of March, 1907.

' JOSEP L. R. HAYDEN.

Witnesses:

HELEN ORFORD, MARGARET E. WOOLLEY. 

